Commit Graph

234 Commits

Author SHA1 Message Date
David Vernet
db52b587c6 bpf, docs: Fix __uninit kfunc doc section
In commit d96d937d7c ("bpf: Add __uninit kfunc annotation"), the
__uninit kfunc annotation was documented in kfuncs.rst. You have to
fully underline a section in rst, or the build will issue a warning that
the title underline is too short:

./Documentation/bpf/kfuncs.rst:104: WARNING: Title underline too short.

2.2.2 __uninit Annotation
--------------------

This patch fixes that title underline.

Fixes: d96d937d7c ("bpf: Add __uninit kfunc annotation")
Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230301194910.602738-2-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-01 16:00:10 -08:00
Joanne Koong
d96d937d7c bpf: Add __uninit kfunc annotation
This patch adds __uninit as a kfunc annotation.

This will be useful for scenarios such as for example in dynptrs,
indicating whether the dynptr should be checked by the verifier as an
initialized or an uninitialized dynptr.

Without this annotation, the alternative would be needing to hard-code
in the verifier the specific kfunc to indicate that arg should be
treated as an uninitialized arg.

Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Link: https://lore.kernel.org/r/20230301154953.641654-7-joannelkoong@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-01 09:55:24 -08:00
Jose E. Marchesi
ae256f9547 bpf, docs: Document BPF insn encoding in term of stored bytes
[Changes from V4:
- s/regs:16/regs:8 in figure.]

[Changes from V3:
- Back to src_reg and dst_reg, since they denote register numbers
  as opposed to the values stored in these registers.]

[Changes from V2:
- Use src and dst consistently in the document.
- Use a more graphical depiction of the 128-bit instruction.
- Remove `Where:' fragment.
- Clarify that unused bits are reserved and shall be zeroed.]

[Changes from V1:
- Use rst literal blocks for figures.
- Avoid using | in the basic instruction/pseudo instruction figure.
- Rebased to today's bpf-next master branch.]

This patch modifies instruction-set.rst so it documents the encoding
of BPF instructions in terms of how the bytes are stored (be it in an
ELF file or as bytes in a memory buffer to be loaded into the kernel
or some other BPF consumer) as opposed to how the instruction looks
like once loaded.

This is hopefully easier to understand by implementors looking to
generate and/or consume bytes conforming BPF instructions.

The patch also clarifies that the unused bytes in a pseudo-instruction
shall be cleared with zeros.

Signed-off-by: Jose E. Marchesi <jose.marchesi@oracle.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/87h6v6i0da.fsf_-_@oracle.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-28 09:55:18 -08:00
Bagas Sanjaya
a07484c083 bpf, docs: Fix link to BTF doc
Ross reported broken link to BTF documentation
(Documentation/bpf/btf.rst) in Documentation/bpf/bpf_devel_QA.rst. The
link in question is written using external link syntax, with the target
refers to BTF doc in reST source (btf.rst), which doesn't exist in
resulting HTML output.

Fix the link by replacing external link syntax with simply writing out
the target doc, which the link will be generated to the correct HTML doc
target.

Fixes: 6736aa793c ("selftests/bpf: Add general instructions for test execution")
Reported-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Ross Zwisler <zwisler@google.com>
Link: https://lore.kernel.org/linux-doc/Y++09LKx25dtR4Ow@google.com/
Link: https://lore.kernel.org/bpf/20230222083530.26136-1-bagasdotme@gmail.com
2023-02-27 21:54:14 +01:00
Tejun Heo
332ea1f697 bpf: Add bpf_cgroup_from_id() kfunc
cgroup ID is an userspace-visible 64bit value uniquely identifying a given
cgroup. As the IDs are used widely, it's useful to be able to look up the
matching cgroups. Add bpf_cgroup_from_id().

v2: Separate out selftest into its own patch as suggested by Alexei.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/Y/bBaG96t0/gQl9/@slm.duckdns.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-23 08:33:05 -08:00
Dave Thaler
746ce76712 bpf, docs: Add explanation of endianness
Document the discussion from the email thread on the IETF bpf list,
where it was explained that the raw format varies by endianness
of the processor.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230220223742.1347-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-22 14:04:55 -08:00
Bagas Sanjaya
e2d323a1f0 Documentation: bpf: Add missing line break separator in node_data struct code block
Stephen Rothwell reported htmldocs warning when merging bpf-next tree,
which was the same warning as reported by kernel test robot:

Documentation/bpf/graph_ds_impl.rst:62: ERROR: Error in "code-block" directive:
maximum 1 argument(s) allowed, 12 supplied.

The error is due to Sphinx confuses node_data struct declaration with
code-block directive option.

Fix the warning by separating the code-block marker with node_data struct
declaration.

Link: https://lore.kernel.org/linux-next/20230215144505.4751d823@canb.auug.org.au/
Link: https://lore.kernel.org/linux-doc/202302151123.wUE5FYFx-lkp@intel.com/
Fixes: c31315c3aa ("bpf, documentation: Add graph documentation for non-owning refs")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20230215123253.41552-3-bagasdotme@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-15 08:43:51 -08:00
Dave Marchevsky
c31315c3aa bpf, documentation: Add graph documentation for non-owning refs
It is difficult to intuit the semantics of owning and non-owning
references from verifier code. In order to keep the high-level details
from being lost in the mailing list, this patch adds documentation
explaining semantics and details.

The target audience of doc added in this patch is folks working on BPF
internals, as there's focus on "what should the verifier do here". Via
reorganization or copy-and-paste, much of the content can probably be
repurposed for BPF program writer audience as well.

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20230214004017.2534011-9-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-13 19:40:53 -08:00
Dave Thaler
d00d5b82f0 bpf, docs: Add note about type convention
Add explanation about use of "u64", "u32", etc. as
the type convention used in BPF documentation.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230127014706.1005-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-08 09:25:26 -08:00
Toke Høiland-Jørgensen
27b53b7364 bpf/docs: Update design QA to be consistent with kfunc lifecycle docs
Cong pointed out that there are some inconsistencies between the BPF design
QA and the lifecycle expectations documentation we added for kfuncs. Let's
update the QA file to be consistent with the kfunc docs, and add references
where it makes sense. Also document that modules may export kfuncs now.

v3:
- Grammar nit + ack from David

v2:
- Fix repeated word (s/defined defined/defined/)

Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20230208164143.286392-1-toke@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-08 09:24:16 -08:00
Dave Thaler
a92adde8d3 bpf, docs: Use consistent names for the same field
Use consistent names for the same field, e.g., 'dst' vs 'dst_reg'.
Previously a mix of terms were used for the same thing in various cases.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230127224555.916-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-07 18:45:43 -08:00
David Vernet
16c294a6aa bpf/docs: Document kfunc lifecycle / stability expectations
BPF kernel <-> kernel API stability has been discussed at length over
the last several weeks and months. Now that we've largely aligned over
kfuncs being the way forward, and BPF helpers being considered
functionally frozen, it's time to document the expectations for kfunc
lifecycles and stability so that everyone (BPF users, kfunc developers,
and maintainers) are all aligned, and have a crystal-clear understanding
of the expectations surrounding kfuncs.

To do that, this patch adds that documentation to the main kfuncs
documentation page via a new 'kfunc lifecycle expectations' section. The
patch describes how decisions are made in the kernel regarding whether
to include, keep, deprecate, or change / remove a kfunc. As described
very overtly in the patch itself, but likely worth highlighting here:

"kfunc stability" does not mean, nor ever will mean, "BPF APIs may block
development elsewhere in the kernel".

Rather, the intention and expectation is for kfuncs to be treated like
EXPORT_SYMBOL_GPL symbols in the kernel. The goal is for kfuncs to be a
safe and valuable option for maintainers and kfunc developers to extend
the kernel, without tying anyone's hands, or imposing any kind of
restrictions on maintainers in the same way that UAPI changes do.

In addition to the 'kfunc lifecycle expectations' section, this patch
also adds documentation for a new KF_DEPRECATED kfunc flag which kfunc
authors or maintainers can choose to add to kfuncs if and when they
decide to deprecate them. Note that as described in the patch itself, a
kfunc need not be deprecated before being changed or removed -- this
flag is simply provided as an available deprecation mechanism for those
that want to provide a deprecation story / timeline to their users.
When necessary, kfuncs may be changed or removed to accommodate changes
elsewhere in the kernel without any deprecation at all.

Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Co-developed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230203155727.793518-2-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-03 09:01:29 -08:00
Eduard Zingerman
cb6018485c docs/bpf: Add description of register liveness tracking algorithm
This is a followup for [1], adds an overview for the register liveness
tracking, covers the following points:
- why register liveness tracking is useful;
- how register parentage chains are constructed;
- how liveness marks are applied using the parentage chains.

[1] https://lore.kernel.org/bpf/CAADnVQKs2i1iuZ5SUGuJtxWVfGYR9kDgYKhq3rNV+kBLQCu7rA@mail.gmail.com/

Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Reviewed-by: Edward Cree <ecree.xilinx@gmail.com>
Link: https://lore.kernel.org/r/20230202125713.821931-2-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-02-02 20:21:59 -08:00
David Vernet
98e6ab7a04 bpf: Document usage of the new __bpf_kfunc macro
Now that the __bpf_kfunc macro has been added to linux/btf.h, include a
blurb about it in the kfuncs.rst file. In order for the macro to
successfully render with .. kernel-doc, we'll also need to add it to the
c_id_attributes array.

Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20230201173016.342758-3-void@manifault.com
2023-02-02 00:25:14 +01:00
Randy Dunlap
1d3cab43f4 Documentation: bpf: correct spelling
Correct spelling problems for Documentation/bpf/ as reported
by codespell.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: bpf@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20230128195046.13327-1-rdunlap@infradead.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-28 12:22:20 -08:00
David Vernet
027bdec893 bpf/docs: Document the nocast aliasing behavior of ___init
When comparing BTF IDs for pointers being passed to kfunc arguments, the
verifier will allow pointer types that are equivalent according to the C
standard. For example, for:

struct bpf_cpumask {
	cpumask_t cpumask;
	refcount_t usage;
};

The verifier will allow a struct bpf_cpumask * to be passed to a kfunc
that takes a const struct cpumask * (cpumask_t is a typedef of struct
cpumask). The exception to this rule is if a type is suffixed with
___init, such as:

struct nf_conn___init {
	struct nf_conn ct;
};

The verifier will _not_ allow a struct nf_conn___init * to be passed to
a kfunc that expects a struct nf_conn *. This patch documents this
behavior in the kfuncs documentation page.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230125143816.721952-8-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-25 07:57:50 -08:00
David Vernet
d94cbde218 bpf/docs: Document how nested trusted fields may be defined
A prior change defined a new BTF_TYPE_SAFE_NESTED macro in the verifier
which allows developers to specify when a pointee field in a struct type
should inherit its parent pointer's trusted status. This patch updates
the kfuncs documentation to specify this macro and how it can be used.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230125143816.721952-7-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-25 07:57:50 -08:00
David Vernet
bdbda39584 bpf/docs: Document cpumask kfuncs in a new file
Now that we've added a series of new cpumask kfuncs, we should document
them so users can easily use them. This patch adds a new cpumasks.rst
file to document them.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20230125143816.721952-6-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-25 07:57:50 -08:00
Dave Thaler
0eb9d19e22 bpf, docs: Fix modulo zero, division by zero, overflow, and underflow
Fix modulo zero, division by zero, overflow, and underflow. Also clarify how
a negative immediate value is used in unsigned division.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20230124001218.827-1-dthaler1968@googlemail.com
2023-01-24 16:46:40 +01:00
Jakub Kicinski
d75858ef10 bpf-next-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
bpf-next 2023-01-04

We've added 45 non-merge commits during the last 21 day(s) which contain
a total of 50 files changed, 1454 insertions(+), 375 deletions(-).

The main changes are:

1) Fixes, improvements and refactoring of parts of BPF verifier's
   state equivalence checks, from Andrii Nakryiko.

2) Fix a few corner cases in libbpf's BTF-to-C converter in particular
   around padding handling and enums, also from Andrii Nakryiko.

3) Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better
  support decap on GRE tunnel devices not operating in collect metadata,
  from Christian Ehrig.

4) Improve x86 JIT's codegen for PROBE_MEM runtime error checks,
   from Dave Marchevsky.

5) Remove the need for trace_printk_lock for bpf_trace_printk
   and bpf_trace_vprintk helpers, from Jiri Olsa.

6) Add proper documentation for BPF_MAP_TYPE_SOCK{MAP,HASH} maps,
   from Maryam Tahhan.

7) Improvements in libbpf's btf_parse_elf error handling, from Changbin Du.

8) Bigger batch of improvements to BPF tracing code samples,
   from Daniel T. Lee.

9) Add LoongArch support to libbpf's bpf_tracing helper header,
   from Hengqi Chen.

10) Fix a libbpf compiler warning in perf_event_open_probe on arm32,
    from Khem Raj.

11) Optimize bpf_local_storage_elem by removing 56 bytes of padding,
    from Martin KaFai Lau.

12) Use pkg-config to locate libelf for resolve_btfids build,
    from Shen Jiamin.

13) Various libbpf improvements around API documentation and errno
    handling, from Xin Liu.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (45 commits)
  libbpf: Return -ENODATA for missing btf section
  libbpf: Add LoongArch support to bpf_tracing.h
  libbpf: Restore errno after pr_warn.
  libbpf: Added the description of some API functions
  libbpf: Fix invalid return address register in s390
  samples/bpf: Use BPF_KSYSCALL macro in syscall tracing programs
  samples/bpf: Fix tracex2 by using BPF_KSYSCALL macro
  samples/bpf: Change _kern suffix to .bpf with syscall tracing program
  samples/bpf: Use vmlinux.h instead of implicit headers in syscall tracing program
  samples/bpf: Use kyscall instead of kprobe in syscall tracing program
  bpf: rename list_head -> graph_root in field info types
  libbpf: fix errno is overwritten after being closed.
  bpf: fix regs_exact() logic in regsafe() to remap IDs correctly
  bpf: perform byte-by-byte comparison only when necessary in regsafe()
  bpf: reject non-exact register type matches in regsafe()
  bpf: generalize MAYBE_NULL vs non-MAYBE_NULL rule
  bpf: reorganize struct bpf_reg_state fields
  bpf: teach refsafe() to take into account ID remapping
  bpf: Remove unused field initialization in bpf's ctl_table
  selftests/bpf: Add jit probe_mem corner case tests to s390x denylist
  ...
====================

Link: https://lore.kernel.org/r/20230105000926.31350-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-04 20:21:25 -08:00
Maryam Tahhan
cafb92d719 docs: BPF_MAP_TYPE_SOCK[MAP|HASH]
Add documentation for BPF_MAP_TYPE_SOCK[MAP|HASH]
including kernel versions introduced, usage
and examples.

Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20221219095512.26534-1-mtahhan@redhat.com
2022-12-20 15:54:05 -08:00
Donald Hunter
d2b497a973 docs/bpf: Reword docs for BPF_MAP_TYPE_SK_STORAGE
Improve the grammar of the function descriptions and highlight
that the key is a socket fd.

Fixes: f3212ad5b7 ("docs/bpf: Add documentation for BPF_MAP_TYPE_SK_STORAGE")
Reported-by: Martin KaFai Lau <martin.lau@linux.dev>
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20221212101600.56026-1-donald.hunter@gmail.com
2022-12-14 18:35:41 +01:00
Donald Hunter
f3212ad5b7 docs/bpf: Add documentation for BPF_MAP_TYPE_SK_STORAGE
Add documentation for the BPF_MAP_TYPE_SK_STORAGE including
kernel version introduced, usage and examples.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221209112401.69319-1-donald.hunter@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-09 09:42:16 -08:00
David Vernet
36aa10ffd6 bpf/docs: Document struct cgroup * kfuncs
bpf_cgroup_acquire(), bpf_cgroup_release(), bpf_cgroup_kptr_get(), and
bpf_cgroup_ancestor(), are kfuncs that were recently added to
kernel/bpf/helpers.c. These are "core" kfuncs in that they're available
for use in any tracepoint or struct_ops BPF program. Though they have no
ABI stability guarantees, we should still document them. This patch adds
a struct cgroup * subsection to the Core kfuncs section which describes
each of these kfuncs.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221207204911.873646-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 17:11:24 -08:00
David Vernet
25c5e92d19 bpf/docs: Document struct task_struct * kfuncs
bpf_task_acquire(), bpf_task_release(), and bpf_task_from_pid() are
kfuncs that were recently added to kernel/bpf/helpers.c. These are
"core" kfuncs in that they're available for use for any tracepoint or
struct_ops BPF program. Though they have no ABI stability guarantees, we
should still document them. This patch adds a new Core kfuncs section to
the BPF kfuncs doc, and adds entries for all of these task kfuncs.

Note that bpf_task_kptr_get() is not documented, as it still returns
NULL while we're working to resolve how it can use RCU to ensure struct
task_struct * lifetime.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221207204911.873646-2-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-07 17:09:13 -08:00
Sreevani Sreejith
8972e18a43 bpf, docs: BPF Iterator Document
Document that describes how BPF iterators work, how to use iterators,
and how to pass parameters in BPF iterators.

Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Sreevani Sreejith <psreep@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221202221710.320810-2-ssreevani@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 16:41:22 -08:00
Yonghong Song
f536256498 docs/bpf: Add KF_RCU documentation
Add proper KF_RCU documentation in kfuncs.rst.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221203184613.478967-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-04 12:52:40 -08:00
Zheng Yejian
bc067cacb6 bpf, docs: Correct the example of BPF_XOR
Refer to description of BPF_XOR, dst_reg should be used but not src_reg
in the examples.

Fixes: be3193cded ("bpf, docs: Add subsections for ALU and JMP instructions")
Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221129134558.2757043-1-zhengyejian1@huawei.com
2022-12-02 21:27:32 +01:00
Maryam Tahhan
2b3e8f6f5b docs/bpf: Add BPF_MAP_TYPE_XSKMAP documentation
Add documentation for BPF_MAP_TYPE_XSKMAP including kernel version introduced,
usage and examples.

Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221123090043.83945-1-mtahhan@redhat.com
2022-11-25 00:33:14 +01:00
Rong Tao
b74344cbed docs/bpf: Update btf selftests program and add link
Commit c64779e24e88("selftests/bpf: Merge most of test_btf into test_progs")
renamed the BTF selftest from 'test_btf.c' to 'prog_tests/btf.c'.

Signed-off-by: Rong Tao <rongtao@cestc.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/tencent_1FA6904156E8E599CAE4ABDBE80F22830106@qq.com
2022-11-25 00:00:15 +01:00
Donald Hunter
539886a32a docs/bpf: Fix sphinx warnings in BPF map docs
Fix duplicate C declaration warnings when using sphinx >= 3.1.

Reported-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Akira Yokosawa <akiyks@gmail.com>
Link: https://lore.kernel.org/bpf/ed4dac84-1b12-5c58-e4de-93ab9ac67c09@gmail.com
Link: https://lore.kernel.org/bpf/20221122143933.91321-1-donald.hunter@gmail.com
2022-11-24 01:05:04 +01:00
Donald Hunter
264c21867a docs/bpf: Document BPF_MAP_TYPE_BLOOM_FILTER
Add documentation for BPF_MAP_TYPE_BLOOM_FILTER including kernel
BPF helper usage, userspace usage and examples.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Joanne Koong <joannelkoong@gmail.com>
Link: https://lore.kernel.org/bpf/20221123141151.54556-1-donald.hunter@gmail.com
2022-11-23 22:47:32 +01:00
Maryam Tahhan
c645eee4d3 docs/bpf: Fix sphinx warnings for devmap
Sphinx version >=3.1 warns about duplicate function declarations in the
DEVMAP documentation. This is because the function name is the same for
kernel and user space BPF progs but the parameters and return types
they take is what differs. This patch moves from using the ``c:function::``
directive to using the ``code-block:: c`` directive. The patches also fix
the indentation for the text associated with the "new" code block delcarations.
The missing support of c:namespace-push:: and c:namespace-pop:: directives by
helper scripts for kernel documentation prevents using the ``c:function::``
directive with proper namespacing.

Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221123092321.88558-3-mtahhan@redhat.com
2022-11-23 22:40:27 +01:00
Maryam Tahhan
3685b0dc0d docs/bpf: Fix sphinx warnings for cpumap
Sphinx version >=3.1 warns about duplicate function declarations in the
CPUMAP documentation. This is because the function name is the same for
kernel and user space BPF progs but the parameters and return types
they take is what differs. This patch moves from using the ``c:function::``
directive to using the ``code-block:: c`` directive. The patches also fix
the indentation for the text associated with the "new" code block delcarations.
The missing support of c:namespace-push:: and c:namespace-pop:: directives by
helper scripts for kernel documentation prevents using the ``c:function::``
directive with proper namespacing.

Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221123092321.88558-2-mtahhan@redhat.com
2022-11-23 22:38:53 +01:00
Donald Hunter
c742cb7c3e docs/bpf: Add table of BPF program types to libbpf docs
Extend the libbpf documentation with a table of program types,
attach points and ELF section names.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20221121121734.98329-1-donald.hunter@gmail.com
2022-11-23 13:31:20 -08:00
David Vernet
3f00c52393 bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncs
Kfuncs currently support specifying the KF_TRUSTED_ARGS flag to signal
to the verifier that it should enforce that a BPF program passes it a
"safe", trusted pointer. Currently, "safe" means that the pointer is
either PTR_TO_CTX, or is refcounted. There may be cases, however, where
the kernel passes a BPF program a safe / trusted pointer to an object
that the BPF program wishes to use as a kptr, but because the object
does not yet have a ref_obj_id from the perspective of the verifier, the
program would be unable to pass it to a KF_ACQUIRE | KF_TRUSTED_ARGS
kfunc.

The solution is to expand the set of pointers that are considered
trusted according to KF_TRUSTED_ARGS, so that programs can invoke kfuncs
with these pointers without getting rejected by the verifier.

There is already a PTR_UNTRUSTED flag that is set in some scenarios,
such as when a BPF program reads a kptr directly from a map
without performing a bpf_kptr_xchg() call. These pointers of course can
and should be rejected by the verifier. Unfortunately, however,
PTR_UNTRUSTED does not cover all the cases for safety that need to
be addressed to adequately protect kfuncs. Specifically, pointers
obtained by a BPF program "walking" a struct are _not_ considered
PTR_UNTRUSTED according to BPF. For example, say that we were to add a
kfunc called bpf_task_acquire(), with KF_ACQUIRE | KF_TRUSTED_ARGS, to
acquire a struct task_struct *. If we only used PTR_UNTRUSTED to signal
that a task was unsafe to pass to a kfunc, the verifier would mistakenly
allow the following unsafe BPF program to be loaded:

SEC("tp_btf/task_newtask")
int BPF_PROG(unsafe_acquire_task,
             struct task_struct *task,
             u64 clone_flags)
{
        struct task_struct *acquired, *nested;

        nested = task->last_wakee;

        /* Would not be rejected by the verifier. */
        acquired = bpf_task_acquire(nested);
        if (!acquired)
                return 0;

        bpf_task_release(acquired);
        return 0;
}

To address this, this patch defines a new type flag called PTR_TRUSTED
which tracks whether a PTR_TO_BTF_ID pointer is safe to pass to a
KF_TRUSTED_ARGS kfunc or a BPF helper function. PTR_TRUSTED pointers are
passed directly from the kernel as a tracepoint or struct_ops callback
argument. Any nested pointer that is obtained from walking a PTR_TRUSTED
pointer is no longer PTR_TRUSTED. From the example above, the struct
task_struct *task argument is PTR_TRUSTED, but the 'nested' pointer
obtained from 'task->last_wakee' is not PTR_TRUSTED.

A subsequent patch will add kfuncs for storing a task kfunc as a kptr,
and then another patch will add selftests to validate.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221120051004.3605026-3-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-20 09:16:21 -08:00
Maryam Tahhan
d1e91173cd bpf, docs: DEVMAPs and XDP_REDIRECT
Add documentation for BPF_MAP_TYPE_DEVMAP and BPF_MAP_TYPE_DEVMAP_HASH
including kernel version introduced, usage and examples.

Add documentation that describes XDP_REDIRECT.

Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221115144921.165483-1-mtahhan@redhat.com
2022-11-18 23:16:31 +01:00
Kumar Kartikeya Dwivedi
a50388dbb3 bpf: Support constant scalar arguments for kfuncs
Allow passing known constant scalars as arguments to kfuncs that do not
represent a size parameter. We use mark_chain_precision for the constant
scalar argument to mark it precise. This makes the search pruning
optimization of verifier more conservative for such kfunc calls, and
each non-distinct argument is considered unequivalent.

We will use this support to then expose a bpf_obj_new function where it
takes the local type ID of a type in program BTF, and returns a
PTR_TO_BTF_ID | MEM_ALLOC to the local type, and allows programs to
allocate their own objects.

Each type ID resolves to a distinct type with a possibly distinct size,
hence the type ID constant matters in terms of program safety and its
precision needs to be checked between old and cur states inside regsafe.
The use of mark_chain_precision enables this.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221118015614.2013203-13-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-17 19:22:13 -08:00
Daniel Müller
383f1a8df8 bpf/docs: Include blank lines between bullet points in bpf_devel_QA.rst
Commit 26a9b433cf ("bpf/docs: Document how to run CI without patch
submission") caused a warning to be generated when compiling the
documentation:

 > bpf_devel_QA.rst:55: WARNING: Unexpected indentation.
 > bpf_devel_QA.rst:56: WARNING: Block quote ends without a blank line

This change fixes the problem by inserting the required blank lines.

Fixes: 26a9b433cf ("bpf/docs: Document how to run CI without patch submission")
Reported-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Akira Yokosawa <akiyks@gmail.com>
Link: https://lore.kernel.org/bpf/20221116174358.2744613-1-deso@posteo.net
2022-11-17 16:26:42 +01:00
Donald Hunter
e0eb60829a docs/bpf: Fix sample code in MAP_TYPE_ARRAY docs
Remove mistaken & from code example in MAP_TYPE_ARRAY docs

Fixes: 1cfa97b30c ("bpf, docs: Document BPF_MAP_TYPE_ARRAY")
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20221115095910.86407-1-donald.hunter@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-15 21:33:47 -08:00
Daniel Müller
26a9b433cf bpf/docs: Document how to run CI without patch submission
This change documents the process for running the BPF CI before
submitting a patch to the upstream mailing list, similar to what happens
if a patch is send to bpf@vger.kernel.org: it builds kernel and
selftests and runs the latter on different architecture (but it notably
does not cover stylistic checks such as cover letter verification).

Running BPF CI this way can help achieve better test coverage ahead of
patch submission than merely running locally (say, using
tools/testing/selftests/bpf/vmtest.sh), as additional architectures may
be covered as well.

Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221114211501.2068684-1-deso@posteo.net
2022-11-15 15:33:27 +01:00
Kumar Kartikeya Dwivedi
1f6d52f1a8 bpf: Remove local kptr references in documentation
We don't want to commit to a specific name for these. Simply call them
allocated objects coming from bpf_obj_new, which is completely clear in
itself.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221114191547.1694267-2-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-14 21:52:45 -08:00
Maryam Tahhan
e662c77536 bpf, docs: Fixup cpumap sphinx >= 3.1 warning
Fixup bpf_map_update_elem() declaration to use a single line.

Reported-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Akira Yokosawa <akiyks@gmail.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20221113103327.3287482-1-mtahhan@redhat.com
2022-11-14 19:10:57 +01:00
Dave Tucker
1cfa97b30c bpf, docs: Document BPF_MAP_TYPE_ARRAY
Add documentation for the BPF_MAP_TYPE_ARRAY including kernel version
introduced, usage and examples. Also document BPF_MAP_TYPE_PERCPU_ARRAY
which is similar.

Co-developed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Maryam Tahhan <mtahhan@redhat.com>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/bpf/20221109174604.31673-2-donald.hunter@gmail.com
2022-11-11 11:37:59 -08:00
Donald Hunter
64488ca57a docs/bpf: Document BPF map types QUEUE and STACK
Add documentation for BPF_MAP_TYPE_QUEUE and BPF_MAP_TYPE_STACK,
including usage and examples.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221108093314.44851-1-donald.hunter@gmail.com
2022-11-11 11:34:39 -08:00
Donald Hunter
f720b84811 docs/bpf: Document BPF ARRAY_OF_MAPS and HASH_OF_MAPS
Add documentation for the ARRAY_OF_MAPS and HASH_OF_MAPS map types,
including usage and examples.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221108102215.47297-1-donald.hunter@gmail.com
2022-11-11 11:32:54 -08:00
Maryam Tahhan
161939abc8 docs/bpf: Document BPF_MAP_TYPE_CPUMAP map
Add documentation for BPF_MAP_TYPE_CPUMAP including
kernel version introduced, usage and examples.

Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Maryam Tahhan <mtahhan@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20221107165207.2682075-2-mtahhan@redhat.com
2022-11-11 11:32:54 -08:00
Donald Hunter
83177c0dca docs/bpf: Document BPF_MAP_TYPE_LPM_TRIE map
Add documentation for BPF_MAP_TYPE_LPM_TRIE including kernel
BPF helper usage, userspace usage and examples.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221101114542.24481-2-donald.hunter@gmail.com
2022-11-11 11:32:49 -08:00
Bagas Sanjaya
25906092ed Documentation: bpf: Escape underscore in BPF type name prefix
Sphinx reported unknown target warning:

Documentation/bpf/bpf_design_QA.rst:329: WARNING: Unknown target name: "bpf".

The warning is caused by BPF type name prefix ("bpf_") which is written
without escaping the trailing underscore.

Escape the underscore to fix the warning. While at it, wrap the
containing paragraph in less than 80 characters.

Fixes: 9805af8d8a ("bpf: Document UAPI details for special BPF types")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20221104123913.50610-1-bagasdotme@gmail.com
2022-11-04 16:10:07 -07:00
Kumar Kartikeya Dwivedi
9805af8d8a bpf: Document UAPI details for special BPF types
The kernel recognizes some special BPF types in map values or local
kptrs. Document that only bpf_spin_lock and bpf_timer will preserve
backwards compatibility, and kptr will preserve backwards compatibility
for the operations on the pointer, not the types supported for such
kptrs.

For local kptrs, document that there are no stability guarantees at all.

Finally, document that 'bpf_' namespace is reserved for adding future
special fields, hence BPF programs must not declare types with such
names in their programs and still expect backwards compatibility.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221103191013.1236066-2-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-03 19:31:13 -07:00
Yonghong Song
d43198017e docs/bpf: Add documentation for new cgroup local storage
Add some descriptions and examples for BPF_MAP_TYPE_CGRP_STORAGE.
Also illustate the major difference between BPF_MAP_TYPE_CGRP_STORAGE
and BPF_MAP_TYPE_CGROUP_STORAGE and recommend to use
BPF_MAP_TYPE_CGRP_STORAGE instead of BPF_MAP_TYPE_CGROUP_STORAGE
in the end.

Acked-by: David Vernet <void@manifault.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20221026042922.676383-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-25 23:19:20 -07:00
Donald Hunter
fb73a20ebe bpf, docs: Reformat BPF maps page to be more readable
Add a more complete introduction, with links to man pages.
Move toctree of map types above usage notes.
Format usage notes to improve readability.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Link: https://lore.kernel.org/r/20221012152715.25073-1-donald.hunter@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-20 18:53:34 -07:00
Linus Torvalds
0326074ff4 Networking changes for 6.1.
Core
 ----
 
  - Introduce and use a single page frag cache for allocating small skb
    heads, clawing back the 10-20% performance regression in UDP flood
    test from previous fixes.
 
  - Run packets which already went thru HW coalescing thru SW GRO.
    This significantly improves TCP segment coalescing and simplifies
    deployments as different workloads benefit from HW or SW GRO.
 
  - Shrink the size of the base zero-copy send structure.
 
  - Move TCP init under a new slow / sleepable version of DO_ONCE().
 
 BPF
 ---
 
  - Add BPF-specific, any-context-safe memory allocator.
 
  - Add helpers/kfuncs for PKCS#7 signature verification from BPF
    programs.
 
  - Define a new map type and related helpers for user space -> kernel
    communication over a ring buffer (BPF_MAP_TYPE_USER_RINGBUF).
 
  - Allow targeting BPF iterators to loop through resources of one
    task/thread.
 
  - Add ability to call selected destructive functions.
    Expose crash_kexec() to allow BPF to trigger a kernel dump.
    Use CAP_SYS_BOOT check on the loading process to judge permissions.
 
  - Enable BPF to collect custom hierarchical cgroup stats efficiently
    by integrating with the rstat framework.
 
  - Support struct arguments for trampoline based programs.
    Only structs with size <= 16B and x86 are supported.
 
  - Invoke cgroup/connect{4,6} programs for unprivileged ICMP ping
    sockets (instead of just TCP and UDP sockets).
 
  - Add a helper for accessing CLOCK_TAI for time sensitive network
    related programs.
 
  - Support accessing network tunnel metadata's flags.
 
  - Make TCP SYN ACK RTO tunable by BPF programs with TCP Fast Open.
 
  - Add support for writing to Netfilter's nf_conn:mark.
 
 Protocols
 ---------
 
  - WiFi: more Extremely High Throughput (EHT) and Multi-Link
    Operation (MLO) work (802.11be, WiFi 7).
 
  - vsock: improve support for SO_RCVLOWAT.
 
  - SMC: support SO_REUSEPORT.
 
  - Netlink: define and document how to use netlink in a "modern" way.
    Support reporting missing attributes via extended ACK.
 
  - IPSec: support collect metadata mode for xfrm interfaces.
 
  - TCPv6: send consistent autoflowlabel in SYN_RECV state
    and RST packets.
 
  - TCP: introduce optional per-netns connection hash table to allow
    better isolation between namespaces (opt-in, at the cost of memory
    and cache pressure).
 
  - MPTCP: support TCP_FASTOPEN_CONNECT.
 
  - Add NEXT-C-SID support in Segment Routing (SRv6) End behavior.
 
  - Adjust IP_UNICAST_IF sockopt behavior for connected UDP sockets.
 
  - Open vSwitch:
    - Allow specifying ifindex of new interfaces.
    - Allow conntrack and metering in non-initial user namespace.
 
  - TLS: support the Korean ARIA-GCM crypto algorithm.
 
  - Remove DECnet support.
 
 Driver API
 ----------
 
  - Allow selecting the conduit interface used by each port
    in DSA switches, at runtime.
 
  - Ethernet Power Sourcing Equipment and Power Device support.
 
  - Add tc-taprio support for queueMaxSDU parameter, i.e. setting
    per traffic class max frame size for time-based packet schedules.
 
  - Support PHY rate matching - adapting between differing host-side
    and link-side speeds.
 
  - Introduce QUSGMII PHY mode and 1000BASE-KX interface mode.
 
  - Validate OF (device tree) nodes for DSA shared ports; make
    phylink-related properties mandatory on DSA and CPU ports.
    Enforcing more uniformity should allow transitioning to phylink.
 
  - Require that flash component name used during update matches one
    of the components for which version is reported by info_get().
 
  - Remove "weight" argument from driver-facing NAPI API as much
    as possible. It's one of those magic knobs which seemed like
    a good idea at the time but is too indirect to use in practice.
 
  - Support offload of TLS connections with 256 bit keys.
 
 New hardware / drivers
 ----------------------
 
  - Ethernet:
    - Microchip KSZ9896 6-port Gigabit Ethernet Switch
    - Renesas Ethernet AVB (EtherAVB-IF) Gen4 SoCs
    - Analog Devices ADIN1110 and ADIN2111 industrial single pair
      Ethernet (10BASE-T1L) MAC+PHY.
    - Rockchip RV1126 Gigabit Ethernet (a version of stmmac IP).
 
  - Ethernet SFPs / modules:
    - RollBall / Hilink / Turris 10G copper SFPs
    - HALNy GPON module
 
  - WiFi:
    - CYW43439 SDIO chipset (brcmfmac)
    - CYW89459 PCIe chipset (brcmfmac)
    - BCM4378 on Apple platforms (brcmfmac)
 
 Drivers
 -------
 
  - CAN:
    - gs_usb: HW timestamp support
 
  - Ethernet PHYs:
    - lan8814: cable diagnostics
 
  - Ethernet NICs:
    - Intel (100G):
      - implement control of FCS/CRC stripping
      - port splitting via devlink
      - L2TPv3 filtering offload
    - nVidia/Mellanox:
      - tunnel offload for sub-functions
      - MACSec offload, w/ Extended packet number and replay
        window offload
      - significantly restructure, and optimize the AF_XDP support,
        align the behavior with other vendors
    - Huawei:
      - configuring DSCP map for traffic class selection
      - querying standard FEC statistics
      - querying SerDes lane number via ethtool
    - Marvell/Cavium:
      - egress priority flow control
      - MACSec offload
    - AMD/SolarFlare:
      - PTP over IPv6 and raw Ethernet
    - small / embedded:
      - ax88772: convert to phylink (to support SFP cages)
      - altera: tse: convert to phylink
      - ftgmac100: support fixed link
      - enetc: standard Ethtool counters
      - macb: ZynqMP SGMII dynamic configuration support
      - tsnep: support multi-queue and use page pool
      - lan743x: Rx IP & TCP checksum offload
      - igc: add xdp frags support to ndo_xdp_xmit
 
  - Ethernet high-speed switches:
    - Marvell (prestera):
      - support SPAN port features (traffic mirroring)
      - nexthop object offloading
    - Microchip (sparx5):
      - multicast forwarding offload
      - QoS queuing offload (tc-mqprio, tc-tbf, tc-ets)
 
  - Ethernet embedded switches:
    - Marvell (mv88e6xxx):
      - support RGMII cmode
    - NXP (felix):
      - standardized ethtool counters
    - Microchip (lan966x):
      - QoS queuing offload (tc-mqprio, tc-tbf, tc-cbs, tc-ets)
      - traffic policing and mirroring
      - link aggregation / bonding offload
      - QUSGMII PHY mode support
 
  - Qualcomm 802.11ax WiFi (ath11k):
    - cold boot calibration support on WCN6750
    - support to connect to a non-transmit MBSSID AP profile
    - enable remain-on-channel support on WCN6750
    - Wake-on-WLAN support for WCN6750
    - support to provide transmit power from firmware via nl80211
    - support to get power save duration for each client
    - spectral scan support for 160 MHz
 
  - MediaTek WiFi (mt76):
    - WiFi-to-Ethernet bridging offload for MT7986 chips
 
  - RealTek WiFi (rtw89):
    - P2P support
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core:

   - Introduce and use a single page frag cache for allocating small skb
     heads, clawing back the 10-20% performance regression in UDP flood
     test from previous fixes.

   - Run packets which already went thru HW coalescing thru SW GRO. This
     significantly improves TCP segment coalescing and simplifies
     deployments as different workloads benefit from HW or SW GRO.

   - Shrink the size of the base zero-copy send structure.

   - Move TCP init under a new slow / sleepable version of DO_ONCE().

  BPF:

   - Add BPF-specific, any-context-safe memory allocator.

   - Add helpers/kfuncs for PKCS#7 signature verification from BPF
     programs.

   - Define a new map type and related helpers for user space -> kernel
     communication over a ring buffer (BPF_MAP_TYPE_USER_RINGBUF).

   - Allow targeting BPF iterators to loop through resources of one
     task/thread.

   - Add ability to call selected destructive functions. Expose
     crash_kexec() to allow BPF to trigger a kernel dump. Use
     CAP_SYS_BOOT check on the loading process to judge permissions.

   - Enable BPF to collect custom hierarchical cgroup stats efficiently
     by integrating with the rstat framework.

   - Support struct arguments for trampoline based programs. Only
     structs with size <= 16B and x86 are supported.

   - Invoke cgroup/connect{4,6} programs for unprivileged ICMP ping
     sockets (instead of just TCP and UDP sockets).

   - Add a helper for accessing CLOCK_TAI for time sensitive network
     related programs.

   - Support accessing network tunnel metadata's flags.

   - Make TCP SYN ACK RTO tunable by BPF programs with TCP Fast Open.

   - Add support for writing to Netfilter's nf_conn:mark.

  Protocols:

   - WiFi: more Extremely High Throughput (EHT) and Multi-Link Operation
     (MLO) work (802.11be, WiFi 7).

   - vsock: improve support for SO_RCVLOWAT.

   - SMC: support SO_REUSEPORT.

   - Netlink: define and document how to use netlink in a "modern" way.
     Support reporting missing attributes via extended ACK.

   - IPSec: support collect metadata mode for xfrm interfaces.

   - TCPv6: send consistent autoflowlabel in SYN_RECV state and RST
     packets.

   - TCP: introduce optional per-netns connection hash table to allow
     better isolation between namespaces (opt-in, at the cost of memory
     and cache pressure).

   - MPTCP: support TCP_FASTOPEN_CONNECT.

   - Add NEXT-C-SID support in Segment Routing (SRv6) End behavior.

   - Adjust IP_UNICAST_IF sockopt behavior for connected UDP sockets.

   - Open vSwitch:
      - Allow specifying ifindex of new interfaces.
      - Allow conntrack and metering in non-initial user namespace.

   - TLS: support the Korean ARIA-GCM crypto algorithm.

   - Remove DECnet support.

  Driver API:

   - Allow selecting the conduit interface used by each port in DSA
     switches, at runtime.

   - Ethernet Power Sourcing Equipment and Power Device support.

   - Add tc-taprio support for queueMaxSDU parameter, i.e. setting per
     traffic class max frame size for time-based packet schedules.

   - Support PHY rate matching - adapting between differing host-side
     and link-side speeds.

   - Introduce QUSGMII PHY mode and 1000BASE-KX interface mode.

   - Validate OF (device tree) nodes for DSA shared ports; make
     phylink-related properties mandatory on DSA and CPU ports.
     Enforcing more uniformity should allow transitioning to phylink.

   - Require that flash component name used during update matches one of
     the components for which version is reported by info_get().

   - Remove "weight" argument from driver-facing NAPI API as much as
     possible. It's one of those magic knobs which seemed like a good
     idea at the time but is too indirect to use in practice.

   - Support offload of TLS connections with 256 bit keys.

  New hardware / drivers:

   - Ethernet:
      - Microchip KSZ9896 6-port Gigabit Ethernet Switch
      - Renesas Ethernet AVB (EtherAVB-IF) Gen4 SoCs
      - Analog Devices ADIN1110 and ADIN2111 industrial single pair
        Ethernet (10BASE-T1L) MAC+PHY.
      - Rockchip RV1126 Gigabit Ethernet (a version of stmmac IP).

   - Ethernet SFPs / modules:
      - RollBall / Hilink / Turris 10G copper SFPs
      - HALNy GPON module

   - WiFi:
      - CYW43439 SDIO chipset (brcmfmac)
      - CYW89459 PCIe chipset (brcmfmac)
      - BCM4378 on Apple platforms (brcmfmac)

  Drivers:

   - CAN:
      - gs_usb: HW timestamp support

   - Ethernet PHYs:
      - lan8814: cable diagnostics

   - Ethernet NICs:
      - Intel (100G):
         - implement control of FCS/CRC stripping
         - port splitting via devlink
         - L2TPv3 filtering offload
      - nVidia/Mellanox:
         - tunnel offload for sub-functions
         - MACSec offload, w/ Extended packet number and replay window
           offload
         - significantly restructure, and optimize the AF_XDP support,
           align the behavior with other vendors
      - Huawei:
         - configuring DSCP map for traffic class selection
         - querying standard FEC statistics
         - querying SerDes lane number via ethtool
      - Marvell/Cavium:
         - egress priority flow control
         - MACSec offload
      - AMD/SolarFlare:
         - PTP over IPv6 and raw Ethernet
      - small / embedded:
         - ax88772: convert to phylink (to support SFP cages)
         - altera: tse: convert to phylink
         - ftgmac100: support fixed link
         - enetc: standard Ethtool counters
         - macb: ZynqMP SGMII dynamic configuration support
         - tsnep: support multi-queue and use page pool
         - lan743x: Rx IP & TCP checksum offload
         - igc: add xdp frags support to ndo_xdp_xmit

   - Ethernet high-speed switches:
      - Marvell (prestera):
         - support SPAN port features (traffic mirroring)
         - nexthop object offloading
      - Microchip (sparx5):
         - multicast forwarding offload
         - QoS queuing offload (tc-mqprio, tc-tbf, tc-ets)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - support RGMII cmode
      - NXP (felix):
         - standardized ethtool counters
      - Microchip (lan966x):
         - QoS queuing offload (tc-mqprio, tc-tbf, tc-cbs, tc-ets)
         - traffic policing and mirroring
         - link aggregation / bonding offload
         - QUSGMII PHY mode support

   - Qualcomm 802.11ax WiFi (ath11k):
      - cold boot calibration support on WCN6750
      - support to connect to a non-transmit MBSSID AP profile
      - enable remain-on-channel support on WCN6750
      - Wake-on-WLAN support for WCN6750
      - support to provide transmit power from firmware via nl80211
      - support to get power save duration for each client
      - spectral scan support for 160 MHz

   - MediaTek WiFi (mt76):
      - WiFi-to-Ethernet bridging offload for MT7986 chips

   - RealTek WiFi (rtw89):
      - P2P support"

* tag 'net-next-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1864 commits)
  eth: pse: add missing static inlines
  once: rename _SLOW to _SLEEPABLE
  net: pse-pd: add regulator based PSE driver
  dt-bindings: net: pse-dt: add bindings for regulator based PoDL PSE controller
  ethtool: add interface to interact with Ethernet Power Equipment
  net: mdiobus: search for PSE nodes by parsing PHY nodes.
  net: mdiobus: fwnode_mdiobus_register_phy() rework error handling
  net: add framework to support Ethernet PSE and PDs devices
  dt-bindings: net: phy: add PoDL PSE property
  net: marvell: prestera: Propagate nh state from hw to kernel
  net: marvell: prestera: Add neighbour cache accounting
  net: marvell: prestera: add stub handler neighbour events
  net: marvell: prestera: Add heplers to interact with fib_notifier_info
  net: marvell: prestera: Add length macros for prestera_ip_addr
  net: marvell: prestera: add delayed wq and flush wq on deinit
  net: marvell: prestera: Add strict cleanup of fib arbiter
  net: marvell: prestera: Add cleanup of allocated fib_nodes
  net: marvell: prestera: Add router nexthops ABI
  eth: octeon: fix build after netif_napi_add() changes
  net/mlx5: E-Switch, Return EBUSY if can't get mode lock
  ...
2022-10-04 13:38:03 -07:00
Bagas Sanjaya
736baae643 Documentation: bpf: Add implementation notes documentations to table of contents
Sphinx reported warnings on missing implementation notes documentations in the
table of contents:

Documentation/bpf/clang-notes.rst: WARNING: document isn't included in any toctree
Documentation/bpf/linux-notes.rst: WARNING: document isn't included in any toctree

Add these documentations to the table of contents (index.rst) of BPF
documentation to fix the warnings.

Link: https://lore.kernel.org/linux-doc/202210020749.yfgDZbRL-lkp@intel.com/
Fixes: 6c7aaffb24 ("bpf, docs: Move Clang notes to a separate file")
Fixes: 6166da0a02 ("bpf, docs: Move legacy packet instructions to a separate file")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20221002032022.24693-1-bagasdotme@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-03 09:16:52 -07:00
Alexei Starovoitov
b502a6fb46 bpf, docs: Delete misformatted table.
Delete misformatted table.

Fixes: 6166da0a02 ("bpf, docs: Move legacy packet instructions to a separate file")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-10-01 08:51:26 -07:00
Dave Thaler
5a8921ba96 bpf, docs: Add TOC and fix formatting.
Add TOC and fix formatting.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20220927185958.14995-5-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-30 13:41:36 -07:00
Dave Thaler
ee159bdbdb bpf, docs: Add Clang note about BPF_ALU
Add Clang note about BPF_ALU.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20220927185958.14995-4-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-30 13:41:25 -07:00
Dave Thaler
6c7aaffb24 bpf, docs: Move Clang notes to a separate file
Move Clang notes to a separate file.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20220927185958.14995-3-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-30 13:41:13 -07:00
Dave Thaler
9a0bf21337 bpf, docs: Linux byteswap note
Add Linux byteswap note.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20220927185958.14995-2-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-30 13:40:59 -07:00
Dave Thaler
6166da0a02 bpf, docs: Move legacy packet instructions to a separate file
Move legacy packet instructions to a separate file.

Signed-off-by: Dave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20220927185958.14995-1-dthaler1968@googlemail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-30 13:40:45 -07:00
Akhil Raj
7f77ebbf75 Delete duplicate words from kernel docs
I have deleted duplicate words like

to, guest, trace, when, we

Signed-off-by: Akhil Raj <lf32.dev@gmail.com>
Link: https://lore.kernel.org/r/20220829065239.4531-1-lf32.dev@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-27 13:21:43 -06:00
Akhil Raj
d2bef8e103 Remove duplicate words inside documentation
I have removed repeated `the` inside the documentation

Signed-off-by: Akhil Raj <lf32.dev@gmail.com>
Link: https://lore.kernel.org/r/20220827145359.32599-1-lf32.dev@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-27 13:21:43 -06:00
Kumar Kartikeya Dwivedi
eed807f626 bpf: Tweak definition of KF_TRUSTED_ARGS
Instead of forcing all arguments to be referenced pointers with non-zero
reg->ref_obj_id, tweak the definition of KF_TRUSTED_ARGS to mean that
only PTR_TO_BTF_ID (and socket types translated to PTR_TO_BTF_ID) have
that constraint, and require their offset to be set to 0.

The rest of pointer types are also accomodated in this definition of
trusted pointers, but with more relaxed rules regarding offsets.

The inherent meaning of setting this flag is that all kfunc pointer
arguments have a guranteed lifetime, and kernel object pointers
(PTR_TO_BTF_ID, PTR_TO_CTX) are passed in their unmodified form (with
offset 0). In general, this is not true for PTR_TO_BTF_ID as it can be
obtained using pointer walks.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://lore.kernel.org/r/cdede0043c47ed7a357f0a915d16f9ce06a1d589.1663778601.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-09-21 19:25:26 -07:00
Jakub Kicinski
3f5f728a72 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Andrii Nakryiko says:

====================
bpf-next 2022-08-17

We've added 45 non-merge commits during the last 14 day(s) which contain
a total of 61 files changed, 986 insertions(+), 372 deletions(-).

The main changes are:

1) New bpf_ktime_get_tai_ns() BPF helper to access CLOCK_TAI, from Kurt
   Kanzenbach and Jesper Dangaard Brouer.

2) Few clean ups and improvements for libbpf 1.0, from Andrii Nakryiko.

3) Expose crash_kexec() as kfunc for BPF programs, from Artem Savkov.

4) Add ability to define sleepable-only kfuncs, from Benjamin Tissoires.

5) Teach libbpf's bpf_prog_load() and bpf_map_create() to gracefully handle
   unsupported names on old kernels, from Hangbin Liu.

6) Allow opting out from auto-attaching BPF programs by libbpf's BPF skeleton,
   from Hao Luo.

7) Relax libbpf's requirement for shared libs to be marked executable, from
   Henqgi Chen.

8) Improve bpf_iter internals handling of error returns, from Hao Luo.

9) Few accommodations in libbpf to support GCC-BPF quirks, from James Hilliard.

10) Fix BPF verifier logic around tracking dynptr ref_obj_id, from Joanne Koong.

11) bpftool improvements to handle full BPF program names better, from Manu
    Bretelle.

12) bpftool fixes around libcap use, from Quentin Monnet.

13) BPF map internals clean ups and improvements around memory allocations,
    from Yafang Shao.

14) Allow to use cgroup_get_from_file() on cgroupv1, allowing BPF cgroup
    iterator to work on cgroupv1, from Yosry Ahmed.

15) BPF verifier internal clean ups, from Dave Marchevsky and Joanne Koong.

16) Various fixes and clean ups for selftests/bpf and vmtest.sh, from Daniel
    Xu, Artem Savkov, Joanne Koong, Andrii Nakryiko, Shibin Koikkara Reeny.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (45 commits)
  selftests/bpf: Few fixes for selftests/bpf built in release mode
  libbpf: Clean up deprecated and legacy aliases
  libbpf: Streamline bpf_attr and perf_event_attr initialization
  libbpf: Fix potential NULL dereference when parsing ELF
  selftests/bpf: Tests libbpf autoattach APIs
  libbpf: Allows disabling auto attach
  selftests/bpf: Fix attach point for non-x86 arches in test_progs/lsm
  libbpf: Making bpf_prog_load() ignore name if kernel doesn't support
  selftests/bpf: Update CI kconfig
  selftests/bpf: Add connmark read test
  selftests/bpf: Add existing connection bpf_*_ct_lookup() test
  bpftool: Clear errno after libcap's checks
  bpf: Clear up confusion in bpf_skb_adjust_room()'s documentation
  bpftool: Fix a typo in a comment
  libbpf: Add names for auxiliary maps
  bpf: Use bpf_map_area_alloc consistently on bpf map creation
  bpf: Make __GFP_NOWARN consistent in bpf map creation
  bpf: Use bpf_map_area_free instread of kvfree
  bpf: Remove unneeded memset in queue_stack_map creation
  libbpf: preserve errno across pr_warn/pr_info/pr_debug
  ...
====================

Link: https://lore.kernel.org/r/20220817215656.1180215-1-andrii@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-17 20:29:36 -07:00
Artem Savkov
4dd48c6f1f bpf: add destructive kfunc flag
Add KF_DESTRUCTIVE flag for destructive functions. Functions with this
flag set will require CAP_SYS_BOOT capabilities.

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Link: https://lore.kernel.org/r/20220810065905.475418-2-asavkov@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-10 09:22:18 -07:00
Benjamin Tissoires
fa96b24204 btf: Add a new kfunc flag which allows to mark a function to be sleepable
This allows to declare a kfunc as sleepable and prevents its use in
a non sleepable program.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Co-developed-by: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Hao Luo <haoluo@google.com>
Link: https://lore.kernel.org/r/20220805214821.1058337-2-haoluo@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-09 09:11:17 -07:00
Paul E. McKenney
8fcf19696a bpf: Update bpf_design_QA.rst to clarify that BTF_ID does not ABIify a function
This patch updates bpf_design_QA.rst to clarify that mentioning a function
to the BTF_ID macro does not make that function become part of the Linux
kernel's ABI.

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220802173913.4170192-3-paulmck@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-04 13:17:24 -07:00
Paul E. McKenney
62fc770d90 bpf: Update bpf_design_QA.rst to clarify that attaching to functions is not ABI
This patch updates bpf_design_QA.rst to clarify that the ability to
attach a BPF program to an arbitrary function in the kernel does not
make that function become part of the Linux kernel's ABI.

[ paulmck: Apply Daniel Borkmann feedback. ]

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220802173913.4170192-2-paulmck@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-04 13:17:24 -07:00
Paul E. McKenney
b9b738eeaf bpf: Update bpf_design_QA.rst to clarify that kprobes is not ABI
This patch updates bpf_design_QA.rst to clarify that the ability to
attach a BPF program to a given point in the kernel code via kprobes
does not make that attachment point be part of the Linux kernel's ABI.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220802173913.4170192-1-paulmck@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-04 13:17:24 -07:00
Kumar Kartikeya Dwivedi
63e564ebd1 bpf: Add documentation for kfuncs
As the usage of kfuncs grows, we are starting to form consensus on the
kinds of attributes and annotations that kfuncs can have. To better help
developers make sense of the various options available at their disposal
to present an unstable API to the BPF users, document the various kfunc
flags and annotations, their expected usage, and explain the process of
defining and registering a kfunc set.

Cc: KP Singh <kpsingh@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220721134245.2450-6-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-21 21:03:16 -07:00
Donald Hunter
979855d302 bpf, docs: document BPF_MAP_TYPE_HASH and variants
Add documentation for BPF_MAP_TYPE_HASH including kernel version
introduced, usage and examples. Document BPF_MAP_TYPE_PERCPU_HASH,
BPF_MAP_TYPE_LRU_HASH and BPF_MAP_TYPE_LRU_PERCPU_HASH variations.

Note that this file is included in the BPF documentation by the glob in
Documentation/bpf/maps.rst

v3:
Fix typos reported by Stanislav Fomichev and Yonghong Song.
Add note about iteration and deletion as requested by Yonghong Song.

v2:
Describe memory allocation semantics as suggested by Stanislav Fomichev.
Fix u64 typo reported by Stanislav Fomichev.
Cut down usage examples to only show usage in context.
Updated patch description to follow style recommendation, reported by
Bagas Sanjaya.

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220718125847.1390-1-donald.hunter@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 10:38:03 -07:00
Indu Bhagat
e5e23424e5 docs/bpf: Update documentation for BTF_KIND_FUNC
The vlen bits in the BTF type of kind BTF_KIND_FUNC are used to convey the
linkage information for functions. The Linux kernel only supports
linkage values of BTF_FUNC_STATIC and BTF_FUNC_GLOBAL at this time.

Signed-off-by: Indu Bhagat <indu.bhagat@oracle.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20220714223310.1140097-1-indu.bhagat@oracle.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 09:42:09 -07:00
Pu Lehui
fb8ddf24c7 bpf, docs: Remove deprecated xsk libbpf APIs description
Since xsk APIs has been removed from libbpf, let's clean up the
BPF docs simutaneously.

Signed-off-by: Pu Lehui <pulehui@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/bpf/20220708042736.669132-1-pulehui@huawei.com
2022-07-08 14:18:50 +02:00
Shahab Vahedi
2f6d1e0f8f bpf, docs: Fix the code formatting in instruction-set
A minor typo fix to include "| BPF_LD" into its previous
code phrase:

``BPF_IND`` | BPF_LD --> ``BPF_IND | BPF_LD``

Signed-off-by: Shahab Vahedi <shahab@synopsys.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/b6120b31-3d1d-bf2d-2f2a-aa768d91257b@synopsys.com
2022-06-24 13:58:32 -07:00
Kosuke Fujimoto
492f99e419 bpf, docs: Fix typo "BFP_ALU" to "BPF_ALU"
"BFP" should be "BPF"

Signed-off-by: Kosuke Fujimoto <fujimotokosuke0@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220609083937.245749-1-fujimotoksouke0@gmail.com
2022-06-09 14:06:41 +02:00
Yonghong Song
61dbd59829 docs/bpf: Update documentation for BTF_KIND_ENUM64 support
Add BTF_KIND_ENUM64 documentation in btf.rst.
Also fixed a typo for section number for BTF_KIND_TYPE_TAG
from 2.2.17 to 2.2.18, and fixed a type size issue for
BTF_KIND_ENUM.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220607062724.3728215-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-07 10:20:44 -07:00
Tiezhu Yang
9a9a90ca13 bpf, docs: Fix typo "respetively" to "respectively"
"respetively" should be "respectively".

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1651139754-4838-4-git-send-email-yangtiezhu@loongson.cn
2022-04-28 17:20:48 +02:00
Tiezhu Yang
c821d80bb8 bpf, docs: BPF_FROM_BE exists as alias for BPF_TO_BE
According to include/uapi/linux/bpf.h:

  #define BPF_FROM_LE	BPF_TO_LE
  #define BPF_FROM_BE	BPF_TO_BE

BPF_FROM_BE exists as alias for BPF_TO_BE instead of BPF_TO_LE.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1651139754-4838-3-git-send-email-yangtiezhu@loongson.cn
2022-04-28 17:20:48 +02:00
Tiezhu Yang
67b97e5842 bpf, docs: Remove duplicated word "instructions"
The word "instructions" is duplicated, remove it.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/1651139754-4838-2-git-send-email-yangtiezhu@loongson.cn
2022-04-28 17:20:48 +02:00
Grant Seltzer
e8c5e1a0f7 libbpf: Improve libbpf API documentation link position
This puts the link for libbpf API documentation into the sidebar
for much easier navigation.

You can preview this change at:

  https://libbpf-test.readthedocs.io/en/latest/

Note that the link is hardcoded to the production version, so you
can see that it self references itself here for now:

  https://libbpf-test.readthedocs.io/en/latest/api.html

This will need to make its way into the libbpf mirror, before being
deployed to libbpf.readthedocs.org

Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220422031050.303984-1-grantseltzer@gmail.com
2022-04-22 16:21:56 +02:00
Jakub Kicinski
8df0136376 docs: netdev: move the netdev-FAQ to the process pages
The documentation for the tip tree is really in quite a similar
spirit to the netdev-FAQ. Move the netdev-FAQ to the process docs
as well.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-03-31 10:49:39 +02:00
Toke Høiland-Jørgensen
1a7551f150 Documentation/bpf: Add documentation for BPF_PROG_RUN
This adds documentation for the BPF_PROG_RUN command; a short overview of
the command itself, and a more verbose description of the "live packet"
mode for XDP introduced in the previous commit.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220309105346.100053-3-toke@redhat.com
2022-03-09 14:19:22 -08:00
Wan Jiabing
43429ea74a bpf, docs: Add a missing colon in verifier.rst
Add a missing colon to fix the document style.

Fixes: 88691e9e1e ("bpf, docs: Split general purpose eBPF documentation out of filter.rst")
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220228080416.1689327-1-wanjiabing@vivo.com
2022-02-28 18:20:35 +01:00
Christoph Hellwig
594d323485 bpf, docs: Better document the atomic instructions
Use proper tables and RST markup to document the atomic instructions
in a structured way.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220131183638.3934982-6-hch@lst.de
2022-02-03 09:29:37 -08:00
Christoph Hellwig
5ca15b8a93 bpf, docs: Better document the extended instruction format
In addition to the normal 64-bit instruction encoding, eBPF also has
a single instruction that uses a second 64-bit bits for a second
immediate value.  Instead of only documenting this format deep down
in the document mention it in the instruction encoding section.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220131183638.3934982-5-hch@lst.de
2022-02-03 09:29:37 -08:00
Christoph Hellwig
1517533627 bpf, docs: Better document the legacy packet access instruction
Use consistent terminology and structured RST elements to better document
these two oddball instructions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220131183638.3934982-4-hch@lst.de
2022-02-03 09:29:31 -08:00
Christoph Hellwig
63d8c242b9 bpf, docs: Better document the regular load and store instructions
Add a separate section and a little intro blurb for the regular load and
store instructions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220131183638.3934982-3-hch@lst.de
2022-02-03 09:23:09 -08:00
Christoph Hellwig
dd33fb571f bpf, docs: Document the byte swapping instructions
Add a section to document the byte swapping instructions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220131183638.3934982-2-hch@lst.de
2022-02-03 09:23:09 -08:00
Yonghong Song
b72903847a docs/bpf: clarify how btf_type_tag gets encoded in the type chain
Clarify where the BTF_KIND_TYPE_TAG gets encoded in the type chain,
so applications and kernel can properly parse them.

Signed-off-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220127154627.665163-1-yhs@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-27 12:03:47 -08:00
Andrii Nakryiko
96c85308ee docs/bpf: update BPF map definition example
Use BTF-defined map definition in the documentation example.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220120060529.1890907-5-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-20 21:19:05 -08:00
Christoph Hellwig
58d8a3fc4a bpf, docs: Fully document the JMP mode modifiers
Add a description for all the modifiers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-7-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig
9e533e22b5 bpf, docs: Fully document the JMP opcodes
Add pseudo-code to document all the different BPF_JMP / BPF_JMP64
opcodes.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-6-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig
03c517ee9e bpf, docs: Fully document the ALU opcodes
Add pseudo-code to document all the different BPF_ALU / BPF_ALU64
opcodes.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-5-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig
894cda554c bpf, docs: Document the opcode classes
Add a description for each opcode class.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-4-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig
be3193cded bpf, docs: Add subsections for ALU and JMP instructions
Add a little more stucture to the ALU/JMP documentation with sections and
improve the example text.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-3-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig
62e4683849 bpf, docs: Add a setion to explain the basic instruction encoding
The eBPF instruction set document does not currently document the basic
instruction encoding.  Add a section to do that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220103183556.41040-2-hch@lst.de
2022-01-05 13:11:26 -08:00
Christoph Hellwig
63d000c3dc bpf, docs: Move the packet access instructions last in instruction-set.rst
The packet access instructions are a convoluted leftover from classic
BPF.  Move them last past the much more important atomic operations,
and improve the rendering of the code example.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211223101906.977624-5-hch@lst.de
2021-12-30 16:34:03 -08:00
Christoph Hellwig
5e4dd19f00 bpf, docs: Generate nicer tables for instruction encodings
Use RST tables that are nicely readable both in plain ascii as well as
in html to render the instruction encodings, and add a few subheadings
to better structure the text.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211223101906.977624-4-hch@lst.de
2021-12-30 16:33:57 -08:00
Christoph Hellwig
41db511a3a bpf, docs: Split the comparism to classic BPF from instruction-set.rst
Split the introductory that explain eBPF vs classic BPF and how it maps
to hardware from the instruction set specification into a standalone
document.  This duplicates a little bit of information but gives us a
useful reference for the eBPF instrution set that is not encumbered by
classic BPF.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211223101906.977624-3-hch@lst.de
2021-12-30 16:31:44 -08:00
Christoph Hellwig
fa86aa77d4 bpf, docs: Fix verifier references
Use normal RST file reference instead of linkage copied from the old filter.rst
document that does not actually work when using HTML output.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211223101906.977624-2-hch@lst.de
2021-12-30 16:31:44 -08:00